CXCL10/CXCR3 overexpression as a biomarker of poor prognosis in patients with stage II colorectal cancer

The CXCL10/CXCR3 axis of inflammatory mediators is one of the most important groups of chemokine axes, which has been proven to be a lymphocyte-associated metastasis mediator in several tumors. The term inflammatory adhesions refers to tumors found to be attached to the surrouding tissues during surgery, although no cancer cell infiltration is later identified on pathological examination. The aim of the present study was to investigate the clinical characteristics of stage II colorectal cancer (CRC) and determine the correlation between the CXCL10/CXCR3 axis, inflammatory adhesions and prognosis. Clinicohistopathological data were collected from 401 CRC patients who had undergone R0 resection. Statistical analysis was performed with SPSS 17.0 software. Immunohistochemistry (IHC) was applied to measure the expression of CXCL10 and CXCR3 in 71 recurrent CRC patients, 72 non-recurrent CRC patients and 10 samples from normal peritumoral tissues, all retrieved from the Tianjin Medical University Cancer Institute and Hospital, Tianjin, China. Inflammatory adhesions, tumor location and size and the number of high-risk factors for reccurrence were more significantly associated with overall survival (OS) rather than disease-free survival in all the patients as determined by the log-rank and Cox's regression hazard analysis. Further analysis demonstrated that only the presence of inflammatory adhesions (P=0.025) was associated with the OS of recurrent patients. Patients with recurrence exhibited higher CXCR3 (P<0.001) and CXCL10 (P<0.001) expression compared with non-recurrent patients, as determined by IHC. The correlation between clinicopathological variables, CXCL10/CXCR3 expression and survival was also analyzed: Inflammatory adhesions and general tumor type (ulcerated vs. elevated) exhibited a significant correlation with CXCR3; however, the expression of CXCL10 was not significantly correlated with tumor location, histological type, size, gender, or preoperative carcinoembryonic antigen and hemoglobin levels. Furthermore, patients exhibiting a high expression of CXCR3 presented with a higher risk of relapse; among those, patients with inflammatory adhesions always exhibited worse survival. However, no such association was identified for CXCL10 expression. In conclusion, CXCR3 expression may be used as a prognostic marker and may contribute to the prediction of clinical outcome in stage II CRC patients.